The grey-headed gull (Chroicocephalus cirrocephalus), also known as the gray-hooded gull, is a small species of gull which breeds patchily in South America and Africa south of the Sahara. It is not truly migratory, but is more widespread in winter. This species has occurred as a rare vagrant to North America, Italy and Spain. As is the case with many gulls, it has traditionally been placed in the genus Larus.
This locally abundant gull breeds in large colonies in reedbeds and marshes, and lays two or three eggs in a nest, which can be on the ground or floating. Like most gulls, it is highly gregarious in winter, both when feeding and in evening roosts. Although it is predominantly coastal or estuarine, it is not a pelagic species, and is rarely seen at sea far from land.
Flocks numbering hundreds or thousands of these gulls can form when the feeding conditions are appropriate.
The grey-headed gull is slightly larger than the black-headed gull at 42 cm length. The summer adult has a pale gray head, a gray body, darker in tone than the black-headed, and red bill and legs. The black tips to the primary wing feathers have conspicuous white "mirrors". The underwing is dark gray with black wingtips. The gray hood is lost in winter, leaving just dark streaks.
Sexes are similar. The South American race is slightly larger and paler-backed than the African subspecies.
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